1. Field of the Invention
The invention relates to the molding of chocolate. Specifically, the disclosed method and apparatus are directed to the continuous molding of chocolate tablets, pieces and the like on a rotary mold.
2. Discussion of the Related Art
Finished chocolates having a desired three-dimensional shape or having an image or design imprinted on a surface are conventionally produced by molding, and are herein referred to as "molded chocolate." The finished chocolate may be a solid block, a hollow shell, or a shell filled with a confectionery material such as fondant, fudge or soft caramel (Chocolate, Cocoa and Confectionery: Science and Technology by Bernard W. Minifie, Third Edition, page 183, herein incorporated by reference in its entirety). Whatever the particular form of the finished chocolate, all are characterized by attributes such as detailed finishes and high surface gloss. Further, these finished chocolates do not require further processing such as enrobing with chocolate, which only provides a home-made look to a product and lacks high gloss and fine surface detail.
Conventional molding typically employs very large numbers of molds, usually made of polycarbonate. These polycarbonate molds are typically flat, approximately 1 inch in height and anywhere from 1 to 2 feet long and 1 to 5 feet in width.
The equipment employed to manipulate and process these molds is very large and among the most complex and expensive of all confectionery production equipment. Mold changeover and mold tooling are also expensive and often make it costly to produce a large variety of shaped chocolate products.
In the typical conventional molding process a chocolate mixture is initially melted at temperatures of about 45.degree. C. and tempered by cooling with agitation to about 29.degree. C. to 30.degree. C. to produce a tempered chocolate. The tempering of the chocolate causes a very small percentage of the fat to form seed crystals which results in a dispersion of these seed crystals throughout the liquid fat phase of the liquid chocolate. The liquid tempered chocolate is then deposited into a polycarbonate mold. The mold is shaken to remove air bubbles and to distribute the chocolate in the mold cavity. These steps are critical to reproducing the detail of the mold surface and to obtaining a glossy finished product surface. Indeed, if the chocolate viscosity is too high or has become significantly partially solidified, the resultant finished chocolate product appearance will be poor. Defects such as air bubbles on the surface, poor gloss and poor or incomplete surface detail are encountered. Thus, to properly mold finished chocolates, it is essential that the final chocolate structure is only developed after filling the molds (i.e., the chocolate must still be liquid when the chocolate is deposited into the molds.)
The mold and chocolate are then cooled and the chocolate hardened, and finally, the set, shaped chocolate is removed from the mold. Removing the chocolate from the mold usually involves turning the molds upside down and deforming them slightly, or striking the mold so that the molded chocolate falls out under its own weight.
These methods place limitations on the size, shape and finish of the final product, and on production efficiency. Conventional chocolate molding processes are among the slowest confectionery production processes for the amount of equipment and space involved. A good production rate would be about 15-20 molds per minute, very good about 20-25 molds per minute and excellent about 25-30 molds per minute. To achieve these high levels of production requires great attention to the process.
Another significant limitation to the molding of finished chocolate products is related to the size of the products. It has long been known in the art that small molded chocolate pieces, on the order of 0.5 grams and smaller, cannot be reliably demolded and this has had the practical effect of limiting confectioners to relatively larger pieces. This problem results from the ratio of surface area in contact with the mold to the mass of the piece being too high in these small pieces. Demolding processes essentially rely on gravity to help remove the pieces from the molds. This is true even in cases where molds are tapped or hammered and in cases where flexible molds might be employed. The smaller mass of a small chocolate piece means less gravitational force to overcome the attractive forces holding the piece into the mold. Thus, a process which provided for continuously molding very small finished chocolate pieces or the like would be a highly desirable advancement in the art.
Processes for continuously molding food products have been disclosed in the prior art, but these processes do not provide for the production of finished molded chocolate.
U.S. Pat. No. 4,059,378, for example, discloses a method of continuously molding chocolate centers, hot sugar masses, fudge, whipped or unwhipped chewing or nougat mass, candy cream and the like which avoids the need for an extruder. These "center" materials are not subject to the same functional requirements as molded chocolate. There is no disclosure of feeding liquid chocolate to the recesses on the mold, and as a practical matter the invention is limited to center manufacture.
The methods and apparatus described in U.S. Pat. No. 4,059,378 do not provide a means to continuously set and mold chocolate tablets, pieces, or the like because the process will not provide an appropriate finish or texture of a finished molded chocolate piece.
Significant functional requirements are demanded of molded chocolate that are not required of centers. The surface of molded chocolate must typically have detailed surface design and glossy finish. The formation of a suitably solidified design with an appropriately glossy finish cannot be performed in a shaping apparatus such as described in U.S. Pat. No. 4,059,378. The apparatus and method of U.S. Pat. No. 4,059,378 are specifically directed towards the molding of confectionery masses, such as the centers or nougat masses and the like specifically noted in the patent. The apparatus and method utilize essentially set confectionery masses, which are then formed by means of an "intake cylinder being operable to press the mass into the molding recesses of the molding cylinder." Clearly the masses are substantially set or solidified, and the patent emphasizes the need for a "gentle molding process which does not impair the original structure of the mass."
By clear contrast, molding processes for finished molded chocolate pieces require the use of liquid chocolate which flows readily into mold cavities and does not have structure. It is the ability of liquid chocolate to flow into mold cavities which ensures good surface detail, good gloss and proper final product texture (i.e., good "snap.")
Published U.K. Pat. Application GB 2,332,387 A describes a method and apparatus for molding food articles. In this method, chocolate halves simultaneously formed in two discrete rollers are pressed together and united in the "nip" between the two rollers. This invention is a further refinement of the long-known technique of roll-forming centers which typically are further processed by panning to apply chocolate coatings or hard sugar shell coatings. The product of these mold-forming techniques does not provide the high quality attributes of finished molded chocolate pieces. In fact, the product of GB 2,332,387 A is a sheet of chocolate articles connected by a continuous web of chocolate which must be removed in an abrasive process known as deflashing. The deflashing process abrades the surface finish of the chocolate articles leaving a rough unfinished appearance. The result is a complex feeding and removal mechanism of uncertain utility.
Other processes describe molding of finished chocolates but do not employ rotary techniques. For example, published International Application WO98/30111, the entire disclosure of which is incorporated herein by reference, describes methods for shaping chocolate products which involve contacting a chocolate composition with a chilled forming device. This application does not describe continuous molding on a rotary mold.